The field of the invention is office supplies and the invention relates more particularly to fasteners for securing a stack of papers together by passing a pair of prongs through a spaced pair of holes near the top edge or side edge of each sheet of paper. Such fasteners are typically referred to by their trademark of "Acco Fasteners." Such fasteners have a lower piece with a pair of metal prongs which may be oriented vertically. The holes in the paper are then passed through the prongs. Next, the top piece is placed over the prongs and over the stack of paper and the prongs are bent over the top piece and affixed to the top piece to secure the papers in place. A large stack of papers fastened with the above-described prongs which are typically thin metal prongs are notorious for becoming unfastened.
Largely because of the possibility of cuts from the thin metal fasteners, attempts have been made to make fasteners which are fabricated from plastic. One such approach is shown in U.S. Pat. No. 5,096,323 which shows a pair of prongs with a series of holes therethrough which fit through openings in a top piece which have locking tang means which pass through the holes in the prongs. They are then folded over and secured by slide locks. Because the holes must be spaced at discreet distances, the unit also can only be tightened in discreet distances.
U.S. Pat. No. 5,257,870 shows a paper fastener which has a pair of notched prongs which pass under first and second clipping parts. Because it is necessary to feed the prongs through a confined space under the right angular part, the release of the part requires two fingers. Furthermore, once the prongs are under the right angular part, it cannot readily be tightened.
U.S. Pat. No. 5,265,968 shows what appears to be a very expensive two-piece unit which is not easy to manipulate.
There is, thus, a need for a stacked paper fastener which may be easily affixed to a stack of papers and with equal ease released and which may be easily tightened against the stack of papers.